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    <ul>
      <li class="level1">
        <a href="">衬衫</a>
        <ul class="level2">
          <li><a class="#none">短袖衬衫</a></li>
          <li><a class="#none">长袖衬衫</a></li>
          <li><a class="#none">短袖T恤</a></li>
          <li><a class="#none">长袖T恤</a></li>
        </ul>
      </li>

      <li class="level1">
        <a href="">卫衣</a>
        <ul class="level2">
          <li><a class="#none">开襟卫衣</a></li>
          <li><a class="#none">套头卫衣</a></li>
          <li><a class="#none">运动卫衣</a></li>
          <li><a class="#none">童装卫衣</a></li>
        </ul>
      </li>

      <li class="level1">
        <a href="">裤子</a>
        <ul class="level2">
          <li><a class="#none">短裤</a></li>
          <li><a class="#none">休闲裤</a></li>
          <li><a class="#none">牛仔裤</a></li>
          <li><a class="#none">免烫卡其裤</a></li>
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